The present invention relates to a method for making a mobile unit accompany an objective person by means of an accompaniment mobile unit for tracking the objective person and relates more concretely to a method for tracking walk.
As a conventional tracking method and apparatus, there is one that tracks the movement of a person by means of an image input device (refer to Japanese Unexamined Patent Publication No. H11-73582).
The tracking apparatus (ambulatory elder following robot) described in Japanese Unexamined Patent Publication No. H11-73582 is described with reference to FIG. 30.
In FIG. 30, an ambulatory elder tracking robot 1 has a GPS receiver 2, a map database 3, a position detection means 4, a notification means 5, a TV camera 6, an image compression means 7, a discrimination means 8, a behavior disorder detection means 9, an obstacle detection sensor 10, an avoidance motion control means 11, a motor 12, and an antitheft part 13.
The operation of the robot 1 is described in outline as follows. The robot 1 preparatorily stores the image information of an ambulatory elder who is the objective person to be tracked by the tracking robot 1 in an image memory of the discrimination means 8. By receiving and image-processing a pickup image of the objective person from the TV camera 6, the objective person is discriminated on the basis of the height of the head, the waist curve condition, the walking manner, the clothes, and so on of the objective person, and the direction of the imaging of the TV camera 6 is controlled on the basis of a discrimination signal for specifying the objective person from the discrimination means 8 to continue the image-pickup by automatic tracking. Otherwise, the robot 1 tracks the objective person by attaching a small transmitter to the objective person and receiving its sent waves.
However, according to the above conventional technology, the objective person is assumed to be the ambulatory elder whose movement speed is slow, and the discrimination or tracking ability is also limited. Moreover, since the movement of the objective person cannot be predicted, it is sometimes impossible to make discrimination. Particularly, when the objective person suddenly changes his or her movement direction, it is impossible to discriminate the objective person, and it is necessary to attach a compact transmitter to the objective person in order to cope with this. Therefore, there is an issue that track of the objective person is lost when the electric wave situation is degraded.
There is a further issue that the image processing and algorithm become complicated because the tracking is performed by image-processing the whole image of a person.
Accordingly, the present invention has the object of solving the issues of the prior art and providing a method for making a mobile unit accompany an objective person, capable of easily predicting and then tracking the walk of the objective person without any special tool or the like regardless of the age and the movement of the objective person.